convert test-output-flex-way-relation-add.cpp to BDD test

Author: lonvia

tests/CMakeLists.txt

@@ -95,7 +95,6 @@ if (WITH_LUA)
     set_test(test-output-flex-types)
     set_test(test-output-flex-update)
     set_test(test-output-flex-validgeom)
-    set_test(test-output-flex-way-relation-add)
     set_test(test-output-flex-way-relation-del)
 
     set_test(test-output-flex-example-configs)